In a substantial number of sewing operation, such as the fabrication of pants, jackets, etc., wherein two pieces of material sewn together it is desired that the beginning and trailing ends of the two fabric plies be sewn so that these ends match upon completion of the sewing operation. The result of evenly matched plies at the end of the sewing operation is desired even though the pieces may be of unequal length when they are received from the cutting room. When pieces of unequal lengths are to be sewn, and to achieve the desired results, it is necessary for the operator to hold back on the shorter of the two plies which therefore advances the effective feed rate of the longer ply. The operation of manually adjusting the effective feed rate of the two plies is difficult to master and therefore requires the employment of a skilled operator. During the sewing operation, it is also possible for the material layers to be mutually displaced. This situation usually applies when materials are used that are difficult to sew to each other, that is, one of the material layers advances more or less than the other layer. For whatever reason it may be, that is, the unequal lengths or the difference in the effective feed length of the materials, due to the type of materials which are to be sewn, the desired result of end matching, both the beginning and trailing ends of the fabric plies is still desired.